Pneumatic apparatus for the separation of minerals



4 Sheets-Sheet 1.

(No Model.)

B. W. HART. PNEUMATIC APPARATUS FOR THE- SEPARATION OF MINERALS, &c. No. 271,450.

Patented. Jan.30, 1883.

WSoZlg EUMZZ Ens. Photo-Lithograph, Washingtum (No Model.) A 4 eeeeeee Sheet 2. B. W. HART.

PNEUMATIC APPARATUS FOR THE SEPARATION OPMINERALS, 6w.

No. 271,450. 'ZQ- Patented Jan.30,1883.

4 Sheets-Sheet 3.

(No Model.)

B. W. HART. A

PNEUMATIC APPARATUS FOR THE SEPARATION OF MINERALS, &c.

No. 271,450, Patented Jan.30, 1883.

- Mi /anion VVO ZZQIIJTarZ (No Model.) 4 Sheets-Sheet 4. B. W. HART.

PNBUMATIG APPARATUS FOR THE SEPARATION OF MINERALS, &c. No. 271,450. Patent-ed Jan.30, 1883.

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A z W 02%? W (a) M/"W NITED STATES ATENT OFFICE.

BENJAMIN \V. HART, OF LONDON, ENGLAND.

SPECIFICATION formingpart of Letters Patent No. 271,450, dated January 30, 1883. Application filed October 27, 1882. (No model.) Patented in England November 15, 188], No. 5,010.

To all whom it may concern:

Be it known that I, BENJAMIN WooLLEY HART, of London, England, have invented new and useful Improvements in Pneumatic MachineryorApp-aratus for theSeparation of Minerals and other Materials of Different Densities, (for which I have obtained a patent in Great Britain, No. 5,010, hearing date th November, 1881 of which the following is a specification, reference being bad to the accompanying drawings.

My invention relates to machines or appara tus of the class described in the specification of British Letters Patent dated April 1, A. 1). 1879, No.1,291, which machines are commonly known as air-jigs or pneumatic ore-separators, and are employed for the separation of associated materials of different densities.

The said invention is illustrated in the accompanying drawings, in which Figure l is .a central vertical section of a machine embodying my improvements, and Fig. 2 is a transverse vertical section of portions of the same on the linear 00, Fig. 1. Fig. 3 is a plan of the said machine with the coverand sieve-bed removed. Fig. 4 is a plan or top view, and Fig. 5 an under side View, of the said cover Fig. 6 is a vertical section of the said cover on the line 3 11 Fig. 4, looking in the direction of the arrow.

Like letters indicate the same parts throughout the drawings.

a represents the main frame of the machine, and b is the box supported thereon. This box, as in the machine or apparatus described in the said former specification, is widest at its rear end or part adjacent to the hopper 0, and its sides I) converge from this rear end to the front of the box, which is comparatively narrow, as shown in Fig. 3. The said box is provided with a sieve-bed, d, which preferably consists of wire-gauze, and which forms an inclined plane from the back to the front of the box. The admission of air to the space below this sieve-bed may be effected and controlled by the aid of suitable valves, which act to regulate the pressure of air required for jigging the material on the said sieve-bed. I prefer to use a Roots blower for compressing the air in my improved machine, for the reason that such a blower produces intermittent currents.

According to my present invention, instead other material under treatment.

of leaving the box open at the top, as described 'in my said former apparatus, the said box is closed by a cover, 6. At the sides the said cover may be cut away or formed with openings of suitable dimensions to permit the discharge over the box-sides I) of the lighter portions of the crushed or stamped mineral or One or more apertures at b of suitable dimensions, are provided at the front or small end of the said box for the discharge of the denser or heavier portions from the sieve-bed (Z. By thus covering the said sieve-bed the air forced through the same is to a certain extent confined, so that 4 its pressure is exerted more advantageously than heretofore in separating the minerals or other materials on the sieve-bed, according to their specific gravity. I further modify the I said apparatus by diminishing the air-space below the sieve-bed. For this purpose I may so construct the portion of the box below the said sieve-bed that there will be only anarrow passage or space for the admission of air immediately under the bed, and extending from the hopper end to the discharge or small end of the box or I may accomplish this result by placing in the box b'a block, f, of wood or other suitable material, whose central portion, f, extends upward into contact with the sieve-bed d, leaving on either side. a passage, g, for the air beneath the sieve-bed. In other words, the elevated portion f of the said blockfdivides into the two parts on the air passage or space between the sieve-bed and the said block f.

h represents an air-channel which may be formed in the lower surface of the blockf, from the rear'to the front of the box, to provide for the passage of air directly to the front or narrow end of the said box.

. The covere of the box issupported upon-the central raised portion,f', ot' the blockf. The thickness or depth of this 'cover is less at the two sides than at the central part, e, so that two converging channels or troughs, i i, corresponding in position with the aforesaid airspaces, are formed at each side of the box for the downward passage of the mineral or material under treatment, the lighter or less dense grains of which travel downward in these pas sages till they escape therefrom at a higher or lower position by the side openings hereinafter described, according to their size, while the heavier or denser grains pass onward to the discharge opening or openings at the front of the box, being thus separated from the.

lighter portions or grains, according to their specific gravity. The downward movement of the specifically lighter portions of the material under treatment to a greater or less distance, according to size, obviates or diminishes the necessity of employing auxiliary machinery, such as that known as sizing machinery, and heretofore generally recognized as indispensable in the treatment of minerals whereof the grains differ in size as well as in specific gravity. The under surface of the cover, which constitutes the upper sides of the said channels, is constructed as shown most clearly in Fig.6 of the drawings-that is to say, it is formed with a series of cells or compartments,

j, closed at their side nearest the center of the cover 0 by the sides of the part (2, but provided with openings at their outer side to permit the discharge of the lighter portions of the mineral or other material over the sides of the box-b. The said cells or compartments, which diminish in width from the rear to the front of the machine, communicate with each other, and are preferably formed with an inclined upper surface, as shown. The said cells may, however, have their upper surface parallel with the under surface, if desired. By thus forming the cover with cells or com partments I provide for arresting or retarding the downward flow of the lighter mineral or other material, so that it will more readily escape at the sides of the box by the aforesaid openings. In the drawings I have shown the cover 0 constructed in two parts; but it will be obvious that the said cover may be formed in one piece.

It I; represent small plates or stops, which form partitions or divisions in the openings between the sides of the box and the sides of the cover, so as to further check the downward flow of the lighter particles of the mineral or other material along the said openings, and thereby increase their tendency to escape over the sides of the box. -Between the lower edge of each of these stops and the sieve-bed there is aspace, as shown in Fig. 2, to permit the continuous downward flow-of the heavier material upon the said bed.

To equalize the distribution of the air passing from the air-chest Zto the sieve-bed, I in some cases prefer to cause it to pass through a perforated plate, as shown at m, Fig. 1.

In some cases I secure to the front or discharge end of the box I) an inclined discharge spout or chute for conducting the mineral or other material to any suitable receptacle. This spout I preferably provide with a valve, so that the discharge of the material may be increased or diminished or entirely stopped.

Having thus fully described my said invention and the manner of performing the same, I wish it understood that I do not restrict myself to a box or apparatus of the shape shown in the accompanying drawings, nor to the combination of the cover with a box which has converging sides, or which has channels or troughs separated from each other by a central block or partition; nor do I now claim broadly the construction of a box with a sieve-bed and converging sides; but

\Vhat I claim is-- 1. The combination, in a pneumatic ore-separator, ot the sieve-bed, with a cover therefor, which is recessed upon its under side to form longitudinal passages, and cut away at its side edges to form lateralopenings, the'lighter material being discharged through the said side openings, and the heavier materials being carried along by the air-blast and discharged at one end of the longitudinal pas sages, substantially as described.

2. A pneumatic ore-separator provided with two covered longitudinal passages converging toward the discharge end of the apparatus, a series of lateral openings along the outer side of each passage, and a sieve-bed, substantially as described.

3. The combination,'in a pneumatic ore'separator, of a sieve-bed with the cover 0, provided upon its under side with the two sets of communicating cells or compartments j, which constitute passages provided with openings along their outer edges, substantially as described.

4. The combination, with the box and sievebed, of the block f, provided with a central raised portion, f, and channels g at the sides thereof, the sieve'bed being supported upon the said block, substantially as described.

5. The combination, with the sieve-bed d, of the cover 8, the passages g and 1', having side openings, and respectively located below and above the. sieve-bed at the two sides of the apparatus, the air-passage L, and an airpassage, It, leading to the discharge endof the machine, substantially as described.

BE NJAMIN \VOOLLEY II ART.

\Vitnesses JOHN DEAN, A. It. SKERTEN, Both of 17 Graccchim'clz Street, London, E. O. 

